XLiii] MATTEUCCIA i57 



39 for J/, struthiopteris (Campbell, l.c^. The series, however, is not continuous, 

 but is interrupted at the insertion of the stalk. Glandular hairs of the Blechnoid 

 type are present though sparingly on the young pinnae. 

 A B 



Fig. 683. Development of the sorus ol Matteuccia internudia. A, B, Z> = sections through 

 the pinna-margin, showing successive stages of the superficial, gradate, non-indusiate sorus, 

 protected only by the curved margin. C=a section parallel to the margin traversing a 

 succession of the distinct non-indusiate sori. (x 125.) 



There are thus good grounds, soral and anatomical, for comparison of 

 Mattenccia intermedia with the simpler Blech- 

 noid Ferns, which go considerably beyond 

 the mere features of external habit. The 

 relations downwards are clearly with the 

 Cyatheoid Ferns, and especially with the 

 ex-indusiate types such as Alsophila and 

 Lophosoria. But on the other hand, it is now 

 more evident than before that the relation- 

 ship upwards, between Matteuccia and the 

 genus Blechmim, so clearly recognised by the 

 early systematists, has the support of more 

 detailed comparison than they had instituted. 

 The new facts appear to suggest that the 

 Blechnoids probably sprang from some early 

 Cyatheoid source, and the nearest indication of a connection is seen in the 

 Fern so happily named by Christensen, Matteuccia intermedia. 



Onoclea Linn. 

 The single species O. sensibilis L. is abundant in the Eastern States of 

 America from Florida northwards. It is also found in Eastern China. It is a 

 creeping swamp plant, with elongated rhizome showing occasional bifurca- 

 tions, bearing isolated leaves which are dimorphic. The sterile leaves are 



>4. Sporangium of Matteuccia 

 iiiteniiedia. ( x 125.) 



